Fabrication of Bistable MEMS Systems for Energy Harvesting

Abstract

Non-linear devices are showing promise for responding to low frequency vibrations for energy harvesting applications [1, 2, 3]. Most MEMS scale energy harvesters take the form of cantilevers operating in their resonant frequency, but such operation is usually confined to the higher frequencies due to their small size [4, 5, 6, 7]. Nonlinear energy harvesters do not operate at their resonant frequency and can harvest lower frequency vibration while still being MEMS scale [3]. One way to introduce non-linearity into a MEMS scale device is to make it bistable [8]. This bi-stability can be created in several ways including shape, magnet repulsion and attraction, and material stress. Each methods benefits and drawbacks will be discussed as it applies to energy harvesting and ease of fabrication.